I live in old fourth ward and it is up and coming and by far the best of the three you asked about. Lakewood and Pittsburgh are still rough around the edges and largely rental communities with tons of foreclosures, abandoned, and borded up houses.
Old fourth ward, on the other hand, has had about six new restaurants open in the last year, new development all over, and a large chunk of the very low income housing, Bedford Pines, is planned to be redeveloped as a medical center. Old fourth ward is on its way to being a spectacular area to live and work in.. You may contact me directly if you would like more information or to take a car ride through all of these areas with me. 404-392-7368.